Well I just joined, and from my few posts you can tell that my thing is burning alive.
My fantazies have very early roots back in Catholic School. I was a very bad little boy and was sent to Mother Superiour's office for punishment where I was told to pull down my pants and bend over the desk infront of a print of Heaven and Hell. Heaven had a few men in robes sitting around Christ, hell was full of naked people burning. As my bare butt got strapped I thought Hell was the more interesting place.
Another factor is that my Church & School were dedicated to the Canadian Martyrs who were burnt at the stake by the Iroquois. There was a large print of this execution, and the good Martyrs were getting burnt nude facing the stake, their butts getting licked by the flames. Also in the Church reading room there was a book about the reformation which had a section about the heretics complete with wood block prints featuring naked people getting burnt at the stake, including one of a very cute young witch getting burnt nude facing the stake with the flames just licking her butt. Burning at the stake nude has been my main sexual kink ever since.
I've role played "BATS" many times both as the executioner, but preferably as the victim. By far my favorite position for this role play is me tied facing the stake with my legs tied up and butt sticking out over the fire. I almost always end up cumming against the stake, and have been burnt to blistering more than once. I loved the burning, but hated the healing. I have been tempted to go all the way to ashes and dust but I'm not really suicidal and keep away from the extreme end to my kink.